Transaction Hash:
Block:
18961183 at Jan-08-2024 08:41:47 AM +UTC
Transaction Fee:
0.001667316960880272 ETH
$3.29
Gas Used:
101,418 Gas / 16.440049704 Gwei
Emitted Events:
| 592 |
TokaToken.Transfer( from=[Receiver] TransparentUpgradeableProxy, to=[Sender] 0xa4aa7e650a9f6ab12ad569e2707c45194aa1024e, value=81600000000000000000000 )
|
| 593 |
TransparentUpgradeableProxy.0x47cee97cb7acd717b3c0aa1435d004cd5b3c8c57d70dbceb4e4458bbd60e39d4( 0x47cee97cb7acd717b3c0aa1435d004cd5b3c8c57d70dbceb4e4458bbd60e39d4, 0x000000000000000000000000a4aa7e650a9f6ab12ad569e2707c45194aa1024e, 0000000000000000000000000000000000000000000011478b7c30abc3000000 )
|
Account State Difference:
| Address | Before | After | State Difference | ||
|---|---|---|---|---|---|
| 0x1eEc8A02...9CD3CB6B6 | |||||
| 0x2a85556a...de1B29F72 | |||||
| 0xA4aA7e65...94AA1024E |
0.834491687043361603 Eth
Nonce: 21
|
0.832824370082481331 Eth
Nonce: 22
| 0.001667316960880272 | ||
|
0xf1568963...B3DF818e1
Miner
| (MEV Builder: 0xf156...8e1) | 11.089587857500117931 Eth | 11.089592928400117931 Eth | 0.0000050709 |
Execution Trace
TransparentUpgradeableProxy.2f52ebb7( )
0x926ee7b5dd8a55abf3eda280dc81558d4fd4951e.2f52ebb7( )-
TokaToken.transfer( to=0xA4aA7e650A9f6AB12Ad569E2707c45194AA1024E, value=81600000000000000000000 ) => ( True )
-
File 1 of 2: TransparentUpgradeableProxy
File 2 of 2: TokaToken
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (interfaces/draft-IERC1822.sol)
pragma solidity ^0.8.0;
/**
* @dev ERC1822: Universal Upgradeable Proxy Standard (UUPS) documents a method for upgradeability through a simplified
* proxy whose upgrades are fully controlled by the current implementation.
*/
interface IERC1822Proxiable {
/**
* @dev Returns the storage slot that the proxiable contract assumes is being used to store the implementation
* address.
*
* IMPORTANT: A proxy pointing at a proxiable contract should not be considered proxiable itself, because this risks
* bricking a proxy that upgrades to it, by delegating to itself until out of gas. Thus it is critical that this
* function revert if invoked through a proxy.
*/
function proxiableUUID() external view returns (bytes32);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (proxy/ERC1967/ERC1967Proxy.sol)
pragma solidity ^0.8.0;
import "../Proxy.sol";
import "./ERC1967Upgrade.sol";
/**
* @dev This contract implements an upgradeable proxy. It is upgradeable because calls are delegated to an
* implementation address that can be changed. This address is stored in storage in the location specified by
* https://eips.ethereum.org/EIPS/eip-1967[EIP1967], so that it doesn't conflict with the storage layout of the
* implementation behind the proxy.
*/
contract ERC1967Proxy is Proxy, ERC1967Upgrade {
/**
* @dev Initializes the upgradeable proxy with an initial implementation specified by `_logic`.
*
* If `_data` is nonempty, it's used as data in a delegate call to `_logic`. This will typically be an encoded
* function call, and allows initializating the storage of the proxy like a Solidity constructor.
*/
constructor(address _logic, bytes memory _data) payable {
assert(_IMPLEMENTATION_SLOT == bytes32(uint256(keccak256("eip1967.proxy.implementation")) - 1));
_upgradeToAndCall(_logic, _data, false);
}
/**
* @dev Returns the current implementation address.
*/
function _implementation() internal view virtual override returns (address impl) {
return ERC1967Upgrade._getImplementation();
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/ERC1967/ERC1967Upgrade.sol)
pragma solidity ^0.8.2;
import "../beacon/IBeacon.sol";
import "../../interfaces/draft-IERC1822.sol";
import "../../utils/Address.sol";
import "../../utils/StorageSlot.sol";
/**
* @dev This abstract contract provides getters and event emitting update functions for
* https://eips.ethereum.org/EIPS/eip-1967[EIP1967] slots.
*
* _Available since v4.1._
*
* @custom:oz-upgrades-unsafe-allow delegatecall
*/
abstract contract ERC1967Upgrade {
// This is the keccak-256 hash of "eip1967.proxy.rollback" subtracted by 1
bytes32 private constant _ROLLBACK_SLOT = 0x4910fdfa16fed3260ed0e7147f7cc6da11a60208b5b9406d12a635614ffd9143;
/**
* @dev Storage slot with the address of the current implementation.
* This is the keccak-256 hash of "eip1967.proxy.implementation" subtracted by 1, and is
* validated in the constructor.
*/
bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
/**
* @dev Emitted when the implementation is upgraded.
*/
event Upgraded(address indexed implementation);
/**
* @dev Returns the current implementation address.
*/
function _getImplementation() internal view returns (address) {
return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
}
/**
* @dev Stores a new address in the EIP1967 implementation slot.
*/
function _setImplementation(address newImplementation) private {
require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
}
/**
* @dev Perform implementation upgrade
*
* Emits an {Upgraded} event.
*/
function _upgradeTo(address newImplementation) internal {
_setImplementation(newImplementation);
emit Upgraded(newImplementation);
}
/**
* @dev Perform implementation upgrade with additional setup call.
*
* Emits an {Upgraded} event.
*/
function _upgradeToAndCall(
address newImplementation,
bytes memory data,
bool forceCall
) internal {
_upgradeTo(newImplementation);
if (data.length > 0 || forceCall) {
Address.functionDelegateCall(newImplementation, data);
}
}
/**
* @dev Perform implementation upgrade with security checks for UUPS proxies, and additional setup call.
*
* Emits an {Upgraded} event.
*/
function _upgradeToAndCallUUPS(
address newImplementation,
bytes memory data,
bool forceCall
) internal {
// Upgrades from old implementations will perform a rollback test. This test requires the new
// implementation to upgrade back to the old, non-ERC1822 compliant, implementation. Removing
// this special case will break upgrade paths from old UUPS implementation to new ones.
if (StorageSlot.getBooleanSlot(_ROLLBACK_SLOT).value) {
_setImplementation(newImplementation);
} else {
try IERC1822Proxiable(newImplementation).proxiableUUID() returns (bytes32 slot) {
require(slot == _IMPLEMENTATION_SLOT, "ERC1967Upgrade: unsupported proxiableUUID");
} catch {
revert("ERC1967Upgrade: new implementation is not UUPS");
}
_upgradeToAndCall(newImplementation, data, forceCall);
}
}
/**
* @dev Storage slot with the admin of the contract.
* This is the keccak-256 hash of "eip1967.proxy.admin" subtracted by 1, and is
* validated in the constructor.
*/
bytes32 internal constant _ADMIN_SLOT = 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103;
/**
* @dev Emitted when the admin account has changed.
*/
event AdminChanged(address previousAdmin, address newAdmin);
/**
* @dev Returns the current admin.
*/
function _getAdmin() internal view virtual returns (address) {
return StorageSlot.getAddressSlot(_ADMIN_SLOT).value;
}
/**
* @dev Stores a new address in the EIP1967 admin slot.
*/
function _setAdmin(address newAdmin) private {
require(newAdmin != address(0), "ERC1967: new admin is the zero address");
StorageSlot.getAddressSlot(_ADMIN_SLOT).value = newAdmin;
}
/**
* @dev Changes the admin of the proxy.
*
* Emits an {AdminChanged} event.
*/
function _changeAdmin(address newAdmin) internal {
emit AdminChanged(_getAdmin(), newAdmin);
_setAdmin(newAdmin);
}
/**
* @dev The storage slot of the UpgradeableBeacon contract which defines the implementation for this proxy.
* This is bytes32(uint256(keccak256('eip1967.proxy.beacon')) - 1)) and is validated in the constructor.
*/
bytes32 internal constant _BEACON_SLOT = 0xa3f0ad74e5423aebfd80d3ef4346578335a9a72aeaee59ff6cb3582b35133d50;
/**
* @dev Emitted when the beacon is upgraded.
*/
event BeaconUpgraded(address indexed beacon);
/**
* @dev Returns the current beacon.
*/
function _getBeacon() internal view returns (address) {
return StorageSlot.getAddressSlot(_BEACON_SLOT).value;
}
/**
* @dev Stores a new beacon in the EIP1967 beacon slot.
*/
function _setBeacon(address newBeacon) private {
require(Address.isContract(newBeacon), "ERC1967: new beacon is not a contract");
require(Address.isContract(IBeacon(newBeacon).implementation()), "ERC1967: beacon implementation is not a contract");
StorageSlot.getAddressSlot(_BEACON_SLOT).value = newBeacon;
}
/**
* @dev Perform beacon upgrade with additional setup call. Note: This upgrades the address of the beacon, it does
* not upgrade the implementation contained in the beacon (see {UpgradeableBeacon-_setImplementation} for that).
*
* Emits a {BeaconUpgraded} event.
*/
function _upgradeBeaconToAndCall(
address newBeacon,
bytes memory data,
bool forceCall
) internal {
_setBeacon(newBeacon);
emit BeaconUpgraded(newBeacon);
if (data.length > 0 || forceCall) {
Address.functionDelegateCall(IBeacon(newBeacon).implementation(), data);
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (proxy/Proxy.sol)
pragma solidity ^0.8.0;
/**
* @dev This abstract contract provides a fallback function that delegates all calls to another contract using the EVM
* instruction `delegatecall`. We refer to the second contract as the _implementation_ behind the proxy, and it has to
* be specified by overriding the virtual {_implementation} function.
*
* Additionally, delegation to the implementation can be triggered manually through the {_fallback} function, or to a
* different contract through the {_delegate} function.
*
* The success and return data of the delegated call will be returned back to the caller of the proxy.
*/
abstract contract Proxy {
/**
* @dev Delegates the current call to `implementation`.
*
* This function does not return to its internal call site, it will return directly to the external caller.
*/
function _delegate(address implementation) internal virtual {
assembly {
// Copy msg.data. We take full control of memory in this inline assembly
// block because it will not return to Solidity code. We overwrite the
// Solidity scratch pad at memory position 0.
calldatacopy(0, 0, calldatasize())
// Call the implementation.
// out and outsize are 0 because we don't know the size yet.
let result := delegatecall(gas(), implementation, 0, calldatasize(), 0, 0)
// Copy the returned data.
returndatacopy(0, 0, returndatasize())
switch result
// delegatecall returns 0 on error.
case 0 {
revert(0, returndatasize())
}
default {
return(0, returndatasize())
}
}
}
/**
* @dev This is a virtual function that should be overriden so it returns the address to which the fallback function
* and {_fallback} should delegate.
*/
function _implementation() internal view virtual returns (address);
/**
* @dev Delegates the current call to the address returned by `_implementation()`.
*
* This function does not return to its internall call site, it will return directly to the external caller.
*/
function _fallback() internal virtual {
_beforeFallback();
_delegate(_implementation());
}
/**
* @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if no other
* function in the contract matches the call data.
*/
fallback() external payable virtual {
_fallback();
}
/**
* @dev Fallback function that delegates calls to the address returned by `_implementation()`. Will run if call data
* is empty.
*/
receive() external payable virtual {
_fallback();
}
/**
* @dev Hook that is called before falling back to the implementation. Can happen as part of a manual `_fallback`
* call, or as part of the Solidity `fallback` or `receive` functions.
*
* If overriden should call `super._beforeFallback()`.
*/
function _beforeFallback() internal virtual {}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (proxy/beacon/IBeacon.sol)
pragma solidity ^0.8.0;
/**
* @dev This is the interface that {BeaconProxy} expects of its beacon.
*/
interface IBeacon {
/**
* @dev Must return an address that can be used as a delegate call target.
*
* {BeaconProxy} will check that this address is a contract.
*/
function implementation() external view returns (address);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (proxy/transparent/TransparentUpgradeableProxy.sol)
pragma solidity ^0.8.0;
import "../ERC1967/ERC1967Proxy.sol";
/**
* @dev This contract implements a proxy that is upgradeable by an admin.
*
* To avoid https://medium.com/nomic-labs-blog/malicious-backdoors-in-ethereum-proxies-62629adf3357[proxy selector
* clashing], which can potentially be used in an attack, this contract uses the
* https://blog.openzeppelin.com/the-transparent-proxy-pattern/[transparent proxy pattern]. This pattern implies two
* things that go hand in hand:
*
* 1. If any account other than the admin calls the proxy, the call will be forwarded to the implementation, even if
* that call matches one of the admin functions exposed by the proxy itself.
* 2. If the admin calls the proxy, it can access the admin functions, but its calls will never be forwarded to the
* implementation. If the admin tries to call a function on the implementation it will fail with an error that says
* "admin cannot fallback to proxy target".
*
* These properties mean that the admin account can only be used for admin actions like upgrading the proxy or changing
* the admin, so it's best if it's a dedicated account that is not used for anything else. This will avoid headaches due
* to sudden errors when trying to call a function from the proxy implementation.
*
* Our recommendation is for the dedicated account to be an instance of the {ProxyAdmin} contract. If set up this way,
* you should think of the `ProxyAdmin` instance as the real administrative interface of your proxy.
*/
contract TransparentUpgradeableProxy is ERC1967Proxy {
/**
* @dev Initializes an upgradeable proxy managed by `_admin`, backed by the implementation at `_logic`, and
* optionally initialized with `_data` as explained in {ERC1967Proxy-constructor}.
*/
constructor(
address _logic,
address admin_,
bytes memory _data
) payable ERC1967Proxy(_logic, _data) {
assert(_ADMIN_SLOT == bytes32(uint256(keccak256("eip1967.proxy.admin")) - 1));
_changeAdmin(admin_);
}
/**
* @dev Modifier used internally that will delegate the call to the implementation unless the sender is the admin.
*/
modifier ifAdmin() {
if (msg.sender == _getAdmin()) {
_;
} else {
_fallback();
}
}
/**
* @dev Returns the current admin.
*
* NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyAdmin}.
*
* TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
* https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
* `0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103`
*/
function admin() external ifAdmin returns (address admin_) {
admin_ = _getAdmin();
}
/**
* @dev Returns the current implementation.
*
* NOTE: Only the admin can call this function. See {ProxyAdmin-getProxyImplementation}.
*
* TIP: To get this value clients can read directly from the storage slot shown below (specified by EIP1967) using the
* https://eth.wiki/json-rpc/API#eth_getstorageat[`eth_getStorageAt`] RPC call.
* `0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc`
*/
function implementation() external ifAdmin returns (address implementation_) {
implementation_ = _implementation();
}
/**
* @dev Changes the admin of the proxy.
*
* Emits an {AdminChanged} event.
*
* NOTE: Only the admin can call this function. See {ProxyAdmin-changeProxyAdmin}.
*/
function changeAdmin(address newAdmin) external virtual ifAdmin {
_changeAdmin(newAdmin);
}
/**
* @dev Upgrade the implementation of the proxy.
*
* NOTE: Only the admin can call this function. See {ProxyAdmin-upgrade}.
*/
function upgradeTo(address newImplementation) external ifAdmin {
_upgradeToAndCall(newImplementation, bytes(""), false);
}
/**
* @dev Upgrade the implementation of the proxy, and then call a function from the new implementation as specified
* by `data`, which should be an encoded function call. This is useful to initialize new storage variables in the
* proxied contract.
*
* NOTE: Only the admin can call this function. See {ProxyAdmin-upgradeAndCall}.
*/
function upgradeToAndCall(address newImplementation, bytes calldata data) external payable ifAdmin {
_upgradeToAndCall(newImplementation, data, true);
}
/**
* @dev Returns the current admin.
*/
function _admin() internal view virtual returns (address) {
return _getAdmin();
}
/**
* @dev Makes sure the admin cannot access the fallback function. See {Proxy-_beforeFallback}.
*/
function _beforeFallback() internal virtual override {
require(msg.sender != _getAdmin(), "TransparentUpgradeableProxy: admin cannot fallback to proxy target");
super._beforeFallback();
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v4.5.0-rc.0) (utils/Address.sol)
pragma solidity ^0.8.1;
/**
* @dev Collection of functions related to the address type
*/
library Address {
/**
* @dev Returns true if `account` is a contract.
*
* [IMPORTANT]
* ====
* It is unsafe to assume that an address for which this function returns
* false is an externally-owned account (EOA) and not a contract.
*
* Among others, `isContract` will return false for the following
* types of addresses:
*
* - an externally-owned account
* - a contract in construction
* - an address where a contract will be created
* - an address where a contract lived, but was destroyed
* ====
*
* [IMPORTANT]
* ====
* You shouldn't rely on `isContract` to protect against flash loan attacks!
*
* Preventing calls from contracts is highly discouraged. It breaks composability, breaks support for smart wallets
* like Gnosis Safe, and does not provide security since it can be circumvented by calling from a contract
* constructor.
* ====
*/
function isContract(address account) internal view returns (bool) {
// This method relies on extcodesize/address.code.length, which returns 0
// for contracts in construction, since the code is only stored at the end
// of the constructor execution.
return account.code.length > 0;
}
/**
* @dev Replacement for Solidity's `transfer`: sends `amount` wei to
* `recipient`, forwarding all available gas and reverting on errors.
*
* https://eips.ethereum.org/EIPS/eip-1884[EIP1884] increases the gas cost
* of certain opcodes, possibly making contracts go over the 2300 gas limit
* imposed by `transfer`, making them unable to receive funds via
* `transfer`. {sendValue} removes this limitation.
*
* https://diligence.consensys.net/posts/2019/09/stop-using-soliditys-transfer-now/[Learn more].
*
* IMPORTANT: because control is transferred to `recipient`, care must be
* taken to not create reentrancy vulnerabilities. Consider using
* {ReentrancyGuard} or the
* https://solidity.readthedocs.io/en/v0.5.11/security-considerations.html#use-the-checks-effects-interactions-pattern[checks-effects-interactions pattern].
*/
function sendValue(address payable recipient, uint256 amount) internal {
require(address(this).balance >= amount, "Address: insufficient balance");
(bool success, ) = recipient.call{value: amount}("");
require(success, "Address: unable to send value, recipient may have reverted");
}
/**
* @dev Performs a Solidity function call using a low level `call`. A
* plain `call` is an unsafe replacement for a function call: use this
* function instead.
*
* If `target` reverts with a revert reason, it is bubbled up by this
* function (like regular Solidity function calls).
*
* Returns the raw returned data. To convert to the expected return value,
* use https://solidity.readthedocs.io/en/latest/units-and-global-variables.html?highlight=abi.decode#abi-encoding-and-decoding-functions[`abi.decode`].
*
* Requirements:
*
* - `target` must be a contract.
* - calling `target` with `data` must not revert.
*
* _Available since v3.1._
*/
function functionCall(address target, bytes memory data) internal returns (bytes memory) {
return functionCall(target, data, "Address: low-level call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`], but with
* `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
return functionCallWithValue(target, data, 0, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but also transferring `value` wei to `target`.
*
* Requirements:
*
* - the calling contract must have an ETH balance of at least `value`.
* - the called Solidity function must be `payable`.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value
) internal returns (bytes memory) {
return functionCallWithValue(target, data, value, "Address: low-level call with value failed");
}
/**
* @dev Same as {xref-Address-functionCallWithValue-address-bytes-uint256-}[`functionCallWithValue`], but
* with `errorMessage` as a fallback revert reason when `target` reverts.
*
* _Available since v3.1._
*/
function functionCallWithValue(
address target,
bytes memory data,
uint256 value,
string memory errorMessage
) internal returns (bytes memory) {
require(address(this).balance >= value, "Address: insufficient balance for call");
require(isContract(target), "Address: call to non-contract");
(bool success, bytes memory returndata) = target.call{value: value}(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(address target, bytes memory data) internal view returns (bytes memory) {
return functionStaticCall(target, data, "Address: low-level static call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a static call.
*
* _Available since v3.3._
*/
function functionStaticCall(
address target,
bytes memory data,
string memory errorMessage
) internal view returns (bytes memory) {
require(isContract(target), "Address: static call to non-contract");
(bool success, bytes memory returndata) = target.staticcall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(address target, bytes memory data) internal returns (bytes memory) {
return functionDelegateCall(target, data, "Address: low-level delegate call failed");
}
/**
* @dev Same as {xref-Address-functionCall-address-bytes-string-}[`functionCall`],
* but performing a delegate call.
*
* _Available since v3.4._
*/
function functionDelegateCall(
address target,
bytes memory data,
string memory errorMessage
) internal returns (bytes memory) {
require(isContract(target), "Address: delegate call to non-contract");
(bool success, bytes memory returndata) = target.delegatecall(data);
return verifyCallResult(success, returndata, errorMessage);
}
/**
* @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
* revert reason using the provided one.
*
* _Available since v4.3._
*/
function verifyCallResult(
bool success,
bytes memory returndata,
string memory errorMessage
) internal pure returns (bytes memory) {
if (success) {
return returndata;
} else {
// Look for revert reason and bubble it up if present
if (returndata.length > 0) {
// The easiest way to bubble the revert reason is using memory via assembly
assembly {
let returndata_size := mload(returndata)
revert(add(32, returndata), returndata_size)
}
} else {
revert(errorMessage);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts v4.4.1 (utils/StorageSlot.sol)
pragma solidity ^0.8.0;
/**
* @dev Library for reading and writing primitive types to specific storage slots.
*
* Storage slots are often used to avoid storage conflict when dealing with upgradeable contracts.
* This library helps with reading and writing to such slots without the need for inline assembly.
*
* The functions in this library return Slot structs that contain a `value` member that can be used to read or write.
*
* Example usage to set ERC1967 implementation slot:
* ```
* contract ERC1967 {
* bytes32 internal constant _IMPLEMENTATION_SLOT = 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc;
*
* function _getImplementation() internal view returns (address) {
* return StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value;
* }
*
* function _setImplementation(address newImplementation) internal {
* require(Address.isContract(newImplementation), "ERC1967: new implementation is not a contract");
* StorageSlot.getAddressSlot(_IMPLEMENTATION_SLOT).value = newImplementation;
* }
* }
* ```
*
* _Available since v4.1 for `address`, `bool`, `bytes32`, and `uint256`._
*/
library StorageSlot {
struct AddressSlot {
address value;
}
struct BooleanSlot {
bool value;
}
struct Bytes32Slot {
bytes32 value;
}
struct Uint256Slot {
uint256 value;
}
/**
* @dev Returns an `AddressSlot` with member `value` located at `slot`.
*/
function getAddressSlot(bytes32 slot) internal pure returns (AddressSlot storage r) {
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `BooleanSlot` with member `value` located at `slot`.
*/
function getBooleanSlot(bytes32 slot) internal pure returns (BooleanSlot storage r) {
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `Bytes32Slot` with member `value` located at `slot`.
*/
function getBytes32Slot(bytes32 slot) internal pure returns (Bytes32Slot storage r) {
assembly {
r.slot := slot
}
}
/**
* @dev Returns an `Uint256Slot` with member `value` located at `slot`.
*/
function getUint256Slot(bytes32 slot) internal pure returns (Uint256Slot storage r) {
assembly {
r.slot := slot
}
}
}
File 2 of 2: TokaToken
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (access/Ownable.sol)
pragma solidity ^0.8.20;
import {Context} from "../utils/Context.sol";
/**
* @dev Contract module which provides a basic access control mechanism, where
* there is an account (an owner) that can be granted exclusive access to
* specific functions.
*
* The initial owner is set to the address provided by the deployer. This can
* later be changed with {transferOwnership}.
*
* This module is used through inheritance. It will make available the modifier
* `onlyOwner`, which can be applied to your functions to restrict their use to
* the owner.
*/
abstract contract Ownable is Context {
address private _owner;
/**
* @dev The caller account is not authorized to perform an operation.
*/
error OwnableUnauthorizedAccount(address account);
/**
* @dev The owner is not a valid owner account. (eg. `address(0)`)
*/
error OwnableInvalidOwner(address owner);
event OwnershipTransferred(address indexed previousOwner, address indexed newOwner);
/**
* @dev Initializes the contract setting the address provided by the deployer as the initial owner.
*/
constructor(address initialOwner) {
if (initialOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(initialOwner);
}
/**
* @dev Throws if called by any account other than the owner.
*/
modifier onlyOwner() {
_checkOwner();
_;
}
/**
* @dev Returns the address of the current owner.
*/
function owner() public view virtual returns (address) {
return _owner;
}
/**
* @dev Throws if the sender is not the owner.
*/
function _checkOwner() internal view virtual {
if (owner() != _msgSender()) {
revert OwnableUnauthorizedAccount(_msgSender());
}
}
/**
* @dev Leaves the contract without owner. It will not be possible to call
* `onlyOwner` functions. Can only be called by the current owner.
*
* NOTE: Renouncing ownership will leave the contract without an owner,
* thereby disabling any functionality that is only available to the owner.
*/
function renounceOwnership() public virtual onlyOwner {
_transferOwnership(address(0));
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Can only be called by the current owner.
*/
function transferOwnership(address newOwner) public virtual onlyOwner {
if (newOwner == address(0)) {
revert OwnableInvalidOwner(address(0));
}
_transferOwnership(newOwner);
}
/**
* @dev Transfers ownership of the contract to a new account (`newOwner`).
* Internal function without access restriction.
*/
function _transferOwnership(address newOwner) internal virtual {
address oldOwner = _owner;
_owner = newOwner;
emit OwnershipTransferred(oldOwner, newOwner);
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (interfaces/draft-IERC6093.sol)
pragma solidity ^0.8.20;
/**
* @dev Standard ERC20 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC20 tokens.
*/
interface IERC20Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientBalance(address sender, uint256 balance, uint256 needed);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC20InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC20InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `spender`’s `allowance`. Used in transfers.
* @param spender Address that may be allowed to operate on tokens without being their owner.
* @param allowance Amount of tokens a `spender` is allowed to operate with.
* @param needed Minimum amount required to perform a transfer.
*/
error ERC20InsufficientAllowance(address spender, uint256 allowance, uint256 needed);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC20InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `spender` to be approved. Used in approvals.
* @param spender Address that may be allowed to operate on tokens without being their owner.
*/
error ERC20InvalidSpender(address spender);
}
/**
* @dev Standard ERC721 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC721 tokens.
*/
interface IERC721Errors {
/**
* @dev Indicates that an address can't be an owner. For example, `address(0)` is a forbidden owner in EIP-20.
* Used in balance queries.
* @param owner Address of the current owner of a token.
*/
error ERC721InvalidOwner(address owner);
/**
* @dev Indicates a `tokenId` whose `owner` is the zero address.
* @param tokenId Identifier number of a token.
*/
error ERC721NonexistentToken(uint256 tokenId);
/**
* @dev Indicates an error related to the ownership over a particular token. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param tokenId Identifier number of a token.
* @param owner Address of the current owner of a token.
*/
error ERC721IncorrectOwner(address sender, uint256 tokenId, address owner);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC721InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC721InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param tokenId Identifier number of a token.
*/
error ERC721InsufficientApproval(address operator, uint256 tokenId);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC721InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC721InvalidOperator(address operator);
}
/**
* @dev Standard ERC1155 Errors
* Interface of the https://eips.ethereum.org/EIPS/eip-6093[ERC-6093] custom errors for ERC1155 tokens.
*/
interface IERC1155Errors {
/**
* @dev Indicates an error related to the current `balance` of a `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
* @param balance Current balance for the interacting account.
* @param needed Minimum amount required to perform a transfer.
* @param tokenId Identifier number of a token.
*/
error ERC1155InsufficientBalance(address sender, uint256 balance, uint256 needed, uint256 tokenId);
/**
* @dev Indicates a failure with the token `sender`. Used in transfers.
* @param sender Address whose tokens are being transferred.
*/
error ERC1155InvalidSender(address sender);
/**
* @dev Indicates a failure with the token `receiver`. Used in transfers.
* @param receiver Address to which tokens are being transferred.
*/
error ERC1155InvalidReceiver(address receiver);
/**
* @dev Indicates a failure with the `operator`’s approval. Used in transfers.
* @param operator Address that may be allowed to operate on tokens without being their owner.
* @param owner Address of the current owner of a token.
*/
error ERC1155MissingApprovalForAll(address operator, address owner);
/**
* @dev Indicates a failure with the `approver` of a token to be approved. Used in approvals.
* @param approver Address initiating an approval operation.
*/
error ERC1155InvalidApprover(address approver);
/**
* @dev Indicates a failure with the `operator` to be approved. Used in approvals.
* @param operator Address that may be allowed to operate on tokens without being their owner.
*/
error ERC1155InvalidOperator(address operator);
/**
* @dev Indicates an array length mismatch between ids and values in a safeBatchTransferFrom operation.
* Used in batch transfers.
* @param idsLength Length of the array of token identifiers
* @param valuesLength Length of the array of token amounts
*/
error ERC1155InvalidArrayLength(uint256 idsLength, uint256 valuesLength);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/ERC20.sol)
pragma solidity ^0.8.20;
import {IERC20} from "./IERC20.sol";
import {IERC20Metadata} from "./extensions/IERC20Metadata.sol";
import {Context} from "../../utils/Context.sol";
import {IERC20Errors} from "../../interfaces/draft-IERC6093.sol";
/**
* @dev Implementation of the {IERC20} interface.
*
* This implementation is agnostic to the way tokens are created. This means
* that a supply mechanism has to be added in a derived contract using {_mint}.
*
* TIP: For a detailed writeup see our guide
* https://forum.openzeppelin.com/t/how-to-implement-erc20-supply-mechanisms/226[How
* to implement supply mechanisms].
*
* The default value of {decimals} is 18. To change this, you should override
* this function so it returns a different value.
*
* We have followed general OpenZeppelin Contracts guidelines: functions revert
* instead returning `false` on failure. This behavior is nonetheless
* conventional and does not conflict with the expectations of ERC20
* applications.
*
* Additionally, an {Approval} event is emitted on calls to {transferFrom}.
* This allows applications to reconstruct the allowance for all accounts just
* by listening to said events. Other implementations of the EIP may not emit
* these events, as it isn't required by the specification.
*/
abstract contract ERC20 is Context, IERC20, IERC20Metadata, IERC20Errors {
mapping(address account => uint256) private _balances;
mapping(address account => mapping(address spender => uint256)) private _allowances;
uint256 private _totalSupply;
string private _name;
string private _symbol;
/**
* @dev Sets the values for {name} and {symbol}.
*
* All two of these values are immutable: they can only be set once during
* construction.
*/
constructor(string memory name_, string memory symbol_) {
_name = name_;
_symbol = symbol_;
}
/**
* @dev Returns the name of the token.
*/
function name() public view virtual returns (string memory) {
return _name;
}
/**
* @dev Returns the symbol of the token, usually a shorter version of the
* name.
*/
function symbol() public view virtual returns (string memory) {
return _symbol;
}
/**
* @dev Returns the number of decimals used to get its user representation.
* For example, if `decimals` equals `2`, a balance of `505` tokens should
* be displayed to a user as `5.05` (`505 / 10 ** 2`).
*
* Tokens usually opt for a value of 18, imitating the relationship between
* Ether and Wei. This is the default value returned by this function, unless
* it's overridden.
*
* NOTE: This information is only used for _display_ purposes: it in
* no way affects any of the arithmetic of the contract, including
* {IERC20-balanceOf} and {IERC20-transfer}.
*/
function decimals() public view virtual returns (uint8) {
return 18;
}
/**
* @dev See {IERC20-totalSupply}.
*/
function totalSupply() public view virtual returns (uint256) {
return _totalSupply;
}
/**
* @dev See {IERC20-balanceOf}.
*/
function balanceOf(address account) public view virtual returns (uint256) {
return _balances[account];
}
/**
* @dev See {IERC20-transfer}.
*
* Requirements:
*
* - `to` cannot be the zero address.
* - the caller must have a balance of at least `value`.
*/
function transfer(address to, uint256 value) public virtual returns (bool) {
address owner = _msgSender();
_transfer(owner, to, value);
return true;
}
/**
* @dev See {IERC20-allowance}.
*/
function allowance(address owner, address spender) public view virtual returns (uint256) {
return _allowances[owner][spender];
}
/**
* @dev See {IERC20-approve}.
*
* NOTE: If `value` is the maximum `uint256`, the allowance is not updated on
* `transferFrom`. This is semantically equivalent to an infinite approval.
*
* Requirements:
*
* - `spender` cannot be the zero address.
*/
function approve(address spender, uint256 value) public virtual returns (bool) {
address owner = _msgSender();
_approve(owner, spender, value);
return true;
}
/**
* @dev See {IERC20-transferFrom}.
*
* Emits an {Approval} event indicating the updated allowance. This is not
* required by the EIP. See the note at the beginning of {ERC20}.
*
* NOTE: Does not update the allowance if the current allowance
* is the maximum `uint256`.
*
* Requirements:
*
* - `from` and `to` cannot be the zero address.
* - `from` must have a balance of at least `value`.
* - the caller must have allowance for ``from``'s tokens of at least
* `value`.
*/
function transferFrom(address from, address to, uint256 value) public virtual returns (bool) {
address spender = _msgSender();
_spendAllowance(from, spender, value);
_transfer(from, to, value);
return true;
}
/**
* @dev Moves a `value` amount of tokens from `from` to `to`.
*
* This internal function is equivalent to {transfer}, and can be used to
* e.g. implement automatic token fees, slashing mechanisms, etc.
*
* Emits a {Transfer} event.
*
* NOTE: This function is not virtual, {_update} should be overridden instead.
*/
function _transfer(address from, address to, uint256 value) internal {
if (from == address(0)) {
revert ERC20InvalidSender(address(0));
}
if (to == address(0)) {
revert ERC20InvalidReceiver(address(0));
}
_update(from, to, value);
}
/**
* @dev Transfers a `value` amount of tokens from `from` to `to`, or alternatively mints (or burns) if `from`
* (or `to`) is the zero address. All customizations to transfers, mints, and burns should be done by overriding
* this function.
*
* Emits a {Transfer} event.
*/
function _update(address from, address to, uint256 value) internal virtual {
if (from == address(0)) {
// Overflow check required: The rest of the code assumes that totalSupply never overflows
_totalSupply += value;
} else {
uint256 fromBalance = _balances[from];
if (fromBalance < value) {
revert ERC20InsufficientBalance(from, fromBalance, value);
}
unchecked {
// Overflow not possible: value <= fromBalance <= totalSupply.
_balances[from] = fromBalance - value;
}
}
if (to == address(0)) {
unchecked {
// Overflow not possible: value <= totalSupply or value <= fromBalance <= totalSupply.
_totalSupply -= value;
}
} else {
unchecked {
// Overflow not possible: balance + value is at most totalSupply, which we know fits into a uint256.
_balances[to] += value;
}
}
emit Transfer(from, to, value);
}
/**
* @dev Creates a `value` amount of tokens and assigns them to `account`, by transferring it from address(0).
* Relies on the `_update` mechanism
*
* Emits a {Transfer} event with `from` set to the zero address.
*
* NOTE: This function is not virtual, {_update} should be overridden instead.
*/
function _mint(address account, uint256 value) internal {
if (account == address(0)) {
revert ERC20InvalidReceiver(address(0));
}
_update(address(0), account, value);
}
/**
* @dev Destroys a `value` amount of tokens from `account`, lowering the total supply.
* Relies on the `_update` mechanism.
*
* Emits a {Transfer} event with `to` set to the zero address.
*
* NOTE: This function is not virtual, {_update} should be overridden instead
*/
function _burn(address account, uint256 value) internal {
if (account == address(0)) {
revert ERC20InvalidSender(address(0));
}
_update(account, address(0), value);
}
/**
* @dev Sets `value` as the allowance of `spender` over the `owner` s tokens.
*
* This internal function is equivalent to `approve`, and can be used to
* e.g. set automatic allowances for certain subsystems, etc.
*
* Emits an {Approval} event.
*
* Requirements:
*
* - `owner` cannot be the zero address.
* - `spender` cannot be the zero address.
*
* Overrides to this logic should be done to the variant with an additional `bool emitEvent` argument.
*/
function _approve(address owner, address spender, uint256 value) internal {
_approve(owner, spender, value, true);
}
/**
* @dev Variant of {_approve} with an optional flag to enable or disable the {Approval} event.
*
* By default (when calling {_approve}) the flag is set to true. On the other hand, approval changes made by
* `_spendAllowance` during the `transferFrom` operation set the flag to false. This saves gas by not emitting any
* `Approval` event during `transferFrom` operations.
*
* Anyone who wishes to continue emitting `Approval` events on the`transferFrom` operation can force the flag to
* true using the following override:
* ```
* function _approve(address owner, address spender, uint256 value, bool) internal virtual override {
* super._approve(owner, spender, value, true);
* }
* ```
*
* Requirements are the same as {_approve}.
*/
function _approve(address owner, address spender, uint256 value, bool emitEvent) internal virtual {
if (owner == address(0)) {
revert ERC20InvalidApprover(address(0));
}
if (spender == address(0)) {
revert ERC20InvalidSpender(address(0));
}
_allowances[owner][spender] = value;
if (emitEvent) {
emit Approval(owner, spender, value);
}
}
/**
* @dev Updates `owner` s allowance for `spender` based on spent `value`.
*
* Does not update the allowance value in case of infinite allowance.
* Revert if not enough allowance is available.
*
* Does not emit an {Approval} event.
*/
function _spendAllowance(address owner, address spender, uint256 value) internal virtual {
uint256 currentAllowance = allowance(owner, spender);
if (currentAllowance != type(uint256).max) {
if (currentAllowance < value) {
revert ERC20InsufficientAllowance(spender, currentAllowance, value);
}
unchecked {
_approve(owner, spender, currentAllowance - value, false);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/ERC20Capped.sol)
pragma solidity ^0.8.20;
import {ERC20} from "../ERC20.sol";
/**
* @dev Extension of {ERC20} that adds a cap to the supply of tokens.
*/
abstract contract ERC20Capped is ERC20 {
uint256 private immutable _cap;
/**
* @dev Total supply cap has been exceeded.
*/
error ERC20ExceededCap(uint256 increasedSupply, uint256 cap);
/**
* @dev The supplied cap is not a valid cap.
*/
error ERC20InvalidCap(uint256 cap);
/**
* @dev Sets the value of the `cap`. This value is immutable, it can only be
* set once during construction.
*/
constructor(uint256 cap_) {
if (cap_ == 0) {
revert ERC20InvalidCap(0);
}
_cap = cap_;
}
/**
* @dev Returns the cap on the token's total supply.
*/
function cap() public view virtual returns (uint256) {
return _cap;
}
/**
* @dev See {ERC20-_update}.
*/
function _update(address from, address to, uint256 value) internal virtual override {
super._update(from, to, value);
if (from == address(0)) {
uint256 maxSupply = cap();
uint256 supply = totalSupply();
if (supply > maxSupply) {
revert ERC20ExceededCap(supply, maxSupply);
}
}
}
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/extensions/IERC20Metadata.sol)
pragma solidity ^0.8.20;
import {IERC20} from "../IERC20.sol";
/**
* @dev Interface for the optional metadata functions from the ERC20 standard.
*/
interface IERC20Metadata is IERC20 {
/**
* @dev Returns the name of the token.
*/
function name() external view returns (string memory);
/**
* @dev Returns the symbol of the token.
*/
function symbol() external view returns (string memory);
/**
* @dev Returns the decimals places of the token.
*/
function decimals() external view returns (uint8);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.0) (token/ERC20/IERC20.sol)
pragma solidity ^0.8.20;
/**
* @dev Interface of the ERC20 standard as defined in the EIP.
*/
interface IERC20 {
/**
* @dev Emitted when `value` tokens are moved from one account (`from`) to
* another (`to`).
*
* Note that `value` may be zero.
*/
event Transfer(address indexed from, address indexed to, uint256 value);
/**
* @dev Emitted when the allowance of a `spender` for an `owner` is set by
* a call to {approve}. `value` is the new allowance.
*/
event Approval(address indexed owner, address indexed spender, uint256 value);
/**
* @dev Returns the value of tokens in existence.
*/
function totalSupply() external view returns (uint256);
/**
* @dev Returns the value of tokens owned by `account`.
*/
function balanceOf(address account) external view returns (uint256);
/**
* @dev Moves a `value` amount of tokens from the caller's account to `to`.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transfer(address to, uint256 value) external returns (bool);
/**
* @dev Returns the remaining number of tokens that `spender` will be
* allowed to spend on behalf of `owner` through {transferFrom}. This is
* zero by default.
*
* This value changes when {approve} or {transferFrom} are called.
*/
function allowance(address owner, address spender) external view returns (uint256);
/**
* @dev Sets a `value` amount of tokens as the allowance of `spender` over the
* caller's tokens.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* IMPORTANT: Beware that changing an allowance with this method brings the risk
* that someone may use both the old and the new allowance by unfortunate
* transaction ordering. One possible solution to mitigate this race
* condition is to first reduce the spender's allowance to 0 and set the
* desired value afterwards:
* https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
*
* Emits an {Approval} event.
*/
function approve(address spender, uint256 value) external returns (bool);
/**
* @dev Moves a `value` amount of tokens from `from` to `to` using the
* allowance mechanism. `value` is then deducted from the caller's
* allowance.
*
* Returns a boolean value indicating whether the operation succeeded.
*
* Emits a {Transfer} event.
*/
function transferFrom(address from, address to, uint256 value) external returns (bool);
}
// SPDX-License-Identifier: MIT
// OpenZeppelin Contracts (last updated v5.0.1) (utils/Context.sol)
pragma solidity ^0.8.20;
/**
* @dev Provides information about the current execution context, including the
* sender of the transaction and its data. While these are generally available
* via msg.sender and msg.data, they should not be accessed in such a direct
* manner, since when dealing with meta-transactions the account sending and
* paying for execution may not be the actual sender (as far as an application
* is concerned).
*
* This contract is only required for intermediate, library-like contracts.
*/
abstract contract Context {
function _msgSender() internal view virtual returns (address) {
return msg.sender;
}
function _msgData() internal view virtual returns (bytes calldata) {
return msg.data;
}
function _contextSuffixLength() internal view virtual returns (uint256) {
return 0;
}
}
// SPDX-License-Identifier: MIT
pragma solidity =0.8.21;
import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import { ERC20Capped } from "@openzeppelin/contracts/token/ERC20/extensions/ERC20Capped.sol";
import { Ownable } from "@openzeppelin/contracts/access/Ownable.sol";
contract TokaToken is ERC20Capped, Ownable {
mapping(address => bool) public isMinter;
mapping(address => bool) public isBurner;
constructor() ERC20("Toka Token", "TOKA") ERC20Capped(1_000_000_000 * (10 ** 18)) Ownable(msg.sender) {}
function addMinter(address _minter) external onlyOwner {
isMinter[_minter] = true;
}
function removeMinter(address _minter) external onlyOwner {
isMinter[_minter] = false;
}
function addBurner(address _burner) external onlyOwner {
isBurner[_burner] = true;
}
function removeBurner(address _burner) external onlyOwner {
isBurner[_burner] = false;
}
function mint(address _to, uint256 _amount) external {
require(isMinter[msg.sender], "Only minter can mint");
_mint(_to, _amount);
}
function burn(address _from, uint256 _amount) external {
require(isBurner[msg.sender], "Only burner can burn");
_burn(_from, _amount);
}
}